Case 1

Biological Growth and Peeling of Paints near Water Source

Algae is extensively present in this section of the roof garden. This defect is found on parapet walls, concrete roof slab and the floor and wall joints. Furthermore, this has escalated to paint peeling of the surfaces. Presence of moisture on these surfaces which under the exposure to sunlight lead to biological growth.

Cause of Defects

This wide growth of algae is attributed to the water stagnation within the parapet wall from a leakage in the plumbing system. The water supply to the irrigation of the roof garden is embedded in the wall within which water can be seen to have been collected, caused by a small leak at the joints of the water piping and fixtures. This has dampened the concrete wall and the floor joints. The moisture also rises up on the wall due to capillary action affecting the cement capping of the parapet wall.